Gravity as Constraint Compliance: A Thermodynamic Framework for Quantum Gravity

Standard quantum mechanics treats quantization as ontological—the substrate itself is discrete at the Planck scale. This paper proposes instead that quantization describes the communication channel, not the substrate. Discreteness is a property of the interface through which we observe, not of reality itself.

Jacobson showed Einstein's equation emerges from horizon thermodynamics. This paper answers the question he left open: what should be quantized? The answer: the constraint interface itself. Null surfaces are low-dimensional bottlenecks where high-dimensional matter dynamics get certified as admissible. The existing metric structure acts as a lattice—it selects which deformations can pass through.

The central object is the Clausius residual Δ_Σ ≡ δQ - TδS. Classical GR corresponds to ⟨Δ_Σ⟩ = 0 (perfect certification). Quantum corrections arise from Var(Δ_Σ) > 0—the interface has finite resolution and can't certify arbitrarily fine distinctions.

Two correction channels emerge: (1) stochastic focusing noise in the Raychaudhuri equation, scaling as ℓ_P²/A, from certification fluctuations; (2) higher-curvature corrections from non-equilibrium certification response. Planck's constant ℏ sets the lattice spacing via ΔA_min ~ Gℏ—one bit of certification precision.

The metric stays classical. What's quantum is the resolution limit of the channel through which we observe it.